Method of and means for making tubes of celluloid and the like



April 22, 1930.

w. MENDEL 1,755,786

METHOD OF AND MEANS FOR MAKING TUBES OF CELLULOID AND THE LIKE FiledNov. 14, 1928 atented pr. 2, i eas WILL MENDEL, 015 BEVERLY, NEW JERSEY,ASSIGNOR T SANITE CORPORATION OF BURLINGTON, NEW JERSEY, A CORPORATIONOF NEW JERSEY ianrnon or n mnans son a ING TUBES OF CELLULOID AND THELIKE Application filed November 14, 1928. Serial No. 319379.

My invention relates to tube forming methods and means of the generalclass claimed in Letters Patent of the United States No. 1,661,451granted to John N. l/Vhitehouse March 6, 1928; whereby a sheet ofsuitable material is rolled, while immersed in a solvent bath having thecapacity to soften the surface of the material, so that successiveconvolutions thereof are rendered coherent and merge in a solid tube.Such material may be celluloid, cellulose-nitrate, cellulose acetate;other products of cellulose; or any suitable substance. Any suitablesolvent may be em-. Y

ployed; for instance, acetone for said celluloid and nitrate, and ethylacetate, or a mixture of alcohol and ether, for said cellulose acetate.Such solvents quickly lose their efficacy by absorption of the sheetmaterial, and moisture from it and the atmosphere, and it is the purposeand efi'ect of my invention to maintain the eficacy of such baths byelimi nation of such solutes therefrom.

For instance, in the formation of tubes but four inches long, forfountain pens, by rolling sheets of celluloid .010 of an inch thick,four inches Wide, and twelve inches long, in a bath of acetone; althoeach sheet is immersed but five seconds, so much of the sheet materialis dissolved in the bath that the initial solvent capacity of the latteris progressively lessened so rapidly; that not more than twenty suchtubes can be made before the solvent capacity of such bath becomesinsufficient to render the successively wound convolutions of thecelluloid coherent. Such ollution occurs even morerapidly if the celuloid includes powdered metal, fish scales, or other pigments which areusually employed to fancifully figure or color the celluloid. Moreover,such an acetone bath is so hygrosco ie that it rapidly absorbs moisturenot only rom the celluloid but-from the su ernatent atmosphere and thebath is rendere ineificient when it absorbs as much as oneand one-halfper cent of water; such absorption being attained in a few hours whensuch atmosphere is only naturally humid.

As hereinafter described,' my invention includes methods of and meansfor forcibly circulating the solvent to and from the sheet materialbeing formed into tubes, and to eliminate the deleterious material fromthe solvent by precipitating such deleterious material and distilling ordecanting the solvent from such precipitate.

My invention includes the various novel features ofprocedure,construction, and arcomprise acetone or any othersuitable solvent 1 oftube material, is maintained at approximately the level 2 in thecontainer 3 in position to submerge the sheet of material 4, which istemporarily supported by the frame plate 5, to be wound on the rotarymandrel 7 under ressure of the idle rollers 8; said mandrel 7 eingconveniently rotated by the chain wheel 10 which is connected by thechain 11 with the wheel 12 which may be turned by the crank 13 Saidframe plate 5 is mounted upon the rock shaft 14 so that the windingmechanism may be lowered to the operative position shown or be raised tothe idle position by the handle 15. The solvent liquid is preferablycontinu-' ously circulated in the container 3 during thewindingoperation by means which moves it to and from the celluloid. Suchcirculating means conveniently includes the inlet conduit 17 and theoutletconduit 18, the latter being controlled by the valve 19.

As shown in Fig. 1, said conduit 18 leads into the still 20 ofsufficient capacity to maintain the desired quantity of the solvent '1above the precipitate 22 which may be revmoved thru the discharge outlet23. under control of the valve 24. Said still may be subjected to heatfrom any suitable source,

1 for instance, the burner 25, so as to volatilize the acetone 1 fromthe residue 22 in said still, which residue includes water, celluloid,and the pigments aforesaid. Of course, in order to thus eliminate waterfrom said solvent, it

is necessary to efiect such distillation at a temperature below 212 F.The gaseous acetone passes from the still thru the conduit 27 to theworm 28 in which it is re -condensed to liquid form and from which it isreceived in the rotary pump 29 which discharges it back into thecontainer 3 thru said inlet conduit 17. Said pump 29 is convenientlyoperated by the electric motor 30 which also operates the air pump 32for cooling said worm 28. Said motor is conveniently energized thru theconductors 34 under control of the switch 35; whereby the circulation ofthe solvent liquid and cooling of the worm may be simultaneouslycontrolled.

As a portion of the liquid contents of the circulatory system aforesaidmust be continuously or intermittently wasted thru the drain 23; I findit convenient to include, in the apparatus, a container 37 for freshsolvent which may beadmitted to the inlet conduit 17 under control ofthe valve 38. However, whether the apparatus includes such container 37or not; it is adapted to forcibly move the solvent bath 1 to and fromthe celluloid 4 which is being formed into a tube and to maintain saidsolvent efficient during of the deleterious material therefrom; butvbecause the freshly distilled acetone has' a greater solvent effect uponthe celluloid, per unit of volume, than commercial acetone.

As it might be assumedthat the aforesaid greater efliciency ofthe'freshly distilled solvent is due to increase in its temperatureincident to the distillation process; I note that repeated tests haveshown that such increased activity is manifest even when the temperature of the freshly distilled acetone delivered into the container 3thru the conduit 17 is lower than the temperature of the bath 1.However, if the acetone is allowed to remain stagnant after suchdistillation, it loses the aforesaid increased solvent eficiency whichcharacterizes it when freshly distilled.

Altho I prefer to eliminate the deleterious matter from the solvent bath1 by continuous circulation and distillation thereof as above described;such deleterious matter may be eliminated, continuously orintermittently, with'respect to the winding operation, by decantation. vFor instance, in Fig. II, the conduits 17 and 18 are part of a closedcirculatory system including the pump 40 and the de-.

canter 41. The water and celluloid, pigments and other deleteriousmatter 22' gravitate to the bottom of said decanter 41 from which theymay be continuously or intermittently discharged thru the conduit 42under control of the valve 43.

be discharged from said still 45 thru the conduit 52 under control ofthe valve53 and the bath be replenished with purifiedsolvent from thecontainer 54, under control of the valve 55.

It may be observed that in each form of my invention above contemplated,the separation and purification of the acetone from the deleteriousmaterial is efl'ected by gravity; the heat of the distillation operationmerely serving to facilitate such gravitative separation.

Therefore, I do not'desire to limit myself to the precise details of themethod and means for forming tubing, as herein set forth, as it isobvious that various modifications may be made therein without departingfrom the essential features of my invention, as defined in the appendedclaims.

I claim:

1. The method of forming tubing, which comprises winding a sheet ofmaterial into a roll while immersed in a solvent initially having thecapacity to dissolve said material, but which capacity is lessened bythe solute from said material, including the step of eliminating thesolute from the solvent material; whereby such capacity of the solventis restored.

2. A method as in claim 1; wherein the solvent is separated from itssolute by gravitation.

3. A method as in claim 1; wherein heat is employed to facilitate theseparation of the solvent from its solute.

'4. A method as in claim 1; wherein, contemporaneously with the windingoperation, the solvent is forcibly circulated to and from the sheetmaterial.

.5. A method as in claim 1; wherein the solvent is forcibly circulated.to and from the sheet material and thru a separator device wherein thesolvent is separated from its solute.

6. A method as in claim 1; wherein the solvent is separated from thesolute, b the action of gravity and heat, during the orcible circulationof the solvent to and from the material for forming the tubing.

7. The method of forming tubingnvhich comprises winding a sheet ofcelluloid into a roll while immersed in a bath of a solvent materialinitially having the capacity to rapidly dissolve the surfaces of saidcelluloid exposed thereto, so that the successively wound convolutionsthereof are rendered coherent and form a solid tube, but said capacit isprogressivel lessened by the amount 02 solute in said ath; and removingsaid solute from said solvent durin the wmding operation; whereby saidcapacity of the solvent is maintained at the proper efliciency forcontinuous use. V 8. Apparatus for forming celluloid tubing, includingmeans for winding a sheet of celluloid in a roll while immersed in asolvent bath and means for forcibly circulating the solventvin said bathduring the winding operation.

9. Apparatus as in claim 8, including solvent circulating and purifyingmeans, comprising a still, and a condenser in cooperative relation withsaid still.

10. Apparatus as in claim 8, including solvent circulating and purifyingmeans, comprising a pump, a still, an a condenser in cooperativerelation with. said still.

11. ,Apparatus as in claim 8, including solvent circulating andpurifying means, comprising a still, and a condenser m cooperativerelation with said still; and means for heat- 1 ing the still above thetemperature of the cooperative relation with said still; meanssurrounding atmosphere.

12. Apparatus as in claim 8, including solvent circulating and purifyingmeans, comprising a pump, a still, and a'condenser in cooperativerelation with said still and means for heating the still above thetemperature of the surrounding atmosphere.

13. Apparatus as in claim 8, including solvent circulating and purifyingmeans, comprising a still, and a condenser in cooperative relation withsaid still; and means for cooling said condenser.

14. Apparatus as in claim 8, including solvent circulating and purifyingmeans, comprising a pump,a still, and a condenser in for cooling saidcondenser; and means for o crating said pump and cooling means, incuding a motor.

15. Apparatus as in claim 8, including solvent circulating and purifyingmeans, comprising a pump, a still, and a condenser in cooperativerelation with said still; means for cooling said condenser; and meansfor o crating said pump and cooling means, inc uding an electric motor;and switch means whereby the means for circulating thesol vent andcooling the condenser may be simultaneously controlled.

16. A method asv in claim 1' wherein the solvent is distilled from thesolute at a tem perature below 212 F.; whereby water is eliminated fromthe solvent.

In testimony whereof, I have hereunto si ed my name ,at Burlington, NewJersey, tlns thirty-first da of October, 1928.

- lV'ILLIAM MENDEL.

